The act of (co-)creating and/or initiating a work (may be a written work, but also an idea, theory or any visual or artistic product).

the act of creating written works; "writing was a form of therapy for him"; "it was a matter of disputed authorship"

the act of initiating a new idea or theory or writing; "the authorship of the theory is disputed"

The quality or state of being an author; function or dignity of an author.

Source; origin; origination; as, the authorship of a book or review, or of an act, or state of affairs.

This term refers to the identity of the creator, period, culture, and source or origin of an object as outlined in the catalogue lot description.